109320821 has 4 divisors (see below), whose sum is σ = 111383532. Its totient is φ = 107258112.

The previous prime is 109320781. The next prime is 109320847. The reversal of 109320821 is 128023901.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 128023901 = 2591 ⋅49411.

It can be written as a sum of positive squares in 2 ways, for example, as 84180625 + 25140196 = 9175^2 + 5014^2 .

It is a cyclic number.

It is not a de Polignac number, because 109320821 - 2¹⁰ = 109319797 is a prime.

It is a super-2 number, since 2×109320821² = 23902083808228082, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (109320881) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1031276 + ... + 1031381.

It is an arithmetic number, because the mean of its divisors is an integer number (27845883).

Almost surely, 2^109320821 is an apocalyptic number.

It is an amenable number.

109320821 is a deficient number, since it is larger than the sum of its proper divisors (2062711).

109320821 is an equidigital number, since it uses as much as digits as its factorization.

109320821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2062710.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 109320821 is about 10455.6597591926. The cubic root of 109320821 is about 478.1538183094.

The spelling of 109320821 in words is "one hundred nine million, three hundred twenty thousand, eight hundred twenty-one".